Preparation of polyfluorinated cycloalk-1-enyl-, alk-1-enyl-, and alkyliodine tetrafluorides using XeF2 in the presence of appropriate Lewis acids as fluorooxidant

Article abstract of DOI:10.1016/j.jfluchem.2005.03.008

Previously unknown polyfluorocyclohexenyl, and acyclic perfluoroalkenyliodine tetrafluorides were prepared in high yields. Perfluorocyclohex-1-enyliodine tetrafluoride was obtained from pentafluoroiodobenzene using XeF₂-NbF₅ in aHF.

Full text of DOI:10.1016/j.jfluchem.2005.03.008

Journal of Fluorine Chemistry 126 (2005) 1036–1043
www.elsevier.com/locate/fluor
Preparation of polyfluorinated cycloalk-1-enyl-, alk-1-enyl-, and
alkyliodine tetrafluorides using XeF2 in the presence of
appropriate Lewis acids as fluorooxidant
b
Hermann Josef Frohn a, , Vadim V. Bardin
*
a Department of Chemistry, Inorganic Chemistry, University Duisburg-Essen, Lotharstr. 1, D-47048 Duisburg, Germany
b N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, SB RAS, Acad. Lavrentjev Ave. 9, 630090 Novosibirsk, Russia
Received 14 February 2005; accepted 4 March 2005
Available online 4 May 2005
Dedicated to Professor Herbert W. Roesky on the occasion of his 70th birthday.
Abstract
Previously unknown polyfluorocyclohexenyl, and acyclic perfluoroalkenyliodine tetrafluorides were prepared in high yields. Perfluoro-
cyclohex-1-enyliodine tetrafluoride was obtained from pentafluoroiodobenzene using XeF2–NbF5 in aHF. The reaction of C6F5I with the
weaker fluorooxidant XeF2–BF3 in 1,1,1,3,3-pentafluorobutane (PFB) yielded C6F5IF2, perfluorocyclohexa-1,4-dienyliodine difluoride,
C6F5IF4, perfluorocyclohexa-1,4, and 1,3-dienyliodine tetrafluoride as intermediate products on parallel reaction routes. Both perfluoroalk-
enyl iodides, cis- and trans-(CF3)2CFCF CFI, reacted with XeF2–BF3 in PFB to give the corresponding perfluoroalkenyliodine tetra-
fluorides, cis- and trans-(CF3)2CFCF CFIF4. Even perfluoroalkyl iodides can be fluorinated by this reagent as was demonstrated by the
preparation of C6F13IF4 from C6F13I. Generally, the CF CIFn fragment (n = 0, 2, or 4) in cyclic or acyclic perfluoroalkenyliodine compounds
RFIFn did not undergo a transformation to the corresponding perfluoroalkyliodine compound. Furthermore, no perfluoroorganoiodine
hexafluorides were detected in reactions with the fluorooxidant XeF2–aHF or BF3 or NbF5.
# 2005 Elsevier B.V. All rights reserved.
Keywords: Xenon difluoride; Fluorine addition; Organoiodine(V) tetrafluorides
1. Introduction
desired alkenyliodine(V) compound, and (c) the transfor-
mation of a suitable organoiodine(V) compound into the
related alkenyliodine(V) compound.
Organic derivatives of iodine(III) and iodine(V) are well-
established compounds with a variety of applications. In
general, the organic chemistry of iodine(V) is much less
developed than the chemistry of iodine(III). The synthesis
and some properties of alkyl- and aryliodine(V) fluorides
were described [1], whereas alkenyliodine(V) compounds
are not known till recently.
A promising route to polyfluoroalkenyliodine tetrafluor-
ides is based on the oxidative addition of fluorine to
polyfluorinated aryliodine(V) derivatives. In 1974, Winfield
and co-workers obtained C6F5IF4 by the reaction of C6F5I
with chlorine trifluoride in perfluorohexane when they
warmed the reaction mixture from ꢀ78 8C to room
temperature [2]. Under similar conditions, the reaction of
either C6F5IF4 or C6F5I with ClF3 in large excess gave
C6ClF8IF4 and C6Cl2F7IF4 (presumably, polyfluorinated
cyclohexenyliodine tetrafluorides), the constitution of which
was not studied [2]. On the other hand, heating of molten
C6F5IF2 with xenon difluoride at 60–65 8C for 3 h led to the
quantitative formation of C6F5IF4 without fluorine addition
Three principal routes to alkenyliodine(V) derivatives
can be discussed: (a) the introduction of an alkenyl group
into a suitable I(V) compound, (b) the oxidation of alkenyl
iodide or an alkenyliodine(III) parent compound to the
* Corresponding author. Tel.: +49 203 379 3310; fax: +49 203 379 2231.
E-mail address: frohn@uni-duisburg.de (H.J. Frohn).
0022-1139/$ – see front matter # 2005 Elsevier B.V. All rights reserved.
doi:10.1016/j.jfluchem.2005.03.008

H.J. Frohn, V.V. Bardin / Journal of Fluorine Chemistry 126 (2005) 1036–1043
1037
Scheme 1.
to the pentafluorophenyl group [3]. In the presence of Lewis
acids the fluorinating ability of xenon difluoride is raised
strongly caused by either the polarisation of the xenon–
fluorine bond in case of a relatively weak fluoride anion
acceptor or the complete ionisation to [FXe][Y] under the
action of a strong fluoride anion acceptor. Previously, we
have successfully employed xenon difluoride in the presence
of Lewis acids (aHF, BF3, SbF5) to convert polyfluoroarenes
bearing either electron donating (SiMe3, SiMe2F,
SiMe2C6F5, GeEt3) or electron withdrawing (F, Cl, Br,
NO2, CN, CF3, SiF3, GeF3, Xe+) substituents into the
corresponding polyfluorocycloalkenyl derivatives [4–9]. In
our present investigation we use this kind of oxidative
fluorinating reaction for the preparation of polyfluoroorga-
noiodine(V) tetrafluorides [10].
parallel to the addition of fluorine to iodine. To get more
insight into the fluorinating process, we studied the reaction
of xenon difluoride with pentafluorophenyliodine difluoride
(6) and with iodopentafluorobenzene (5) in the presence of
the weak Lewis acid boron trifluoride in the inert solvent
1,1,1,3,3-pentafluorobutane (PFB) [11].
Xenon difluoride (one equivalent) did not react with a
solution of 6 in PFB at 0 8C within 5 min, but a slow
bubbling of BF3 at 0 8C caused the immediate formation of a
white precipitate and vigorous evolution of gas. After
stirring at 20 8C for 2 h the mother liquor contained
perfluorocyclohexa-1,4-dienyliodine difluoride (7), C6F5IF4
(1), and dienes C6F7IF4 (2, 3) beside unchanged penta-
fluorophenyliodine difluoride (6). The subsequent addition
of XeF2 (four equivalents) caused dissolution of the
precipitate and finally perfluorinated cyclohexadienyliodine
tetrafluoride 2 and cyclohexenyliodine tetrafluoride 4
(70:30) were obtained in quantitative yield (Scheme 3).
The reaction of 5 with XeF2 (four equivalents) in PFB in
the presence of boron trifluoride at ꢂ20 8C gave a solution of
perfluorocyclohexa-1,4-dienyliodine difluoride (7), C6F5IF4
(1), and dienes C6F7IF4 (2, 3) beside a trace of 4, however
aryl iodide 5 and aryliodine difluoride 6 were not detected.
The further reaction with XeF2 (additional one equivalent)
under BF3-catalysis resulted in the conversion of 7 and 1 into
cyclic alkenyliodine tetrafluorides 2, 3, and 4 in 90% overall
yield (Scheme 4).
2. Results and discussion
2.1. Preparation of polyfluorocycloalk-1-enyliodine
tetrafluorides
When a suspension of C6F5IF4 (1) in aHF was treated
with two equivalents of XeF2 at ꢀ5 to 20 8C, xenon evolved
and perfluorinated cyclohexa-1,4-dienyliodine tetrafluoride
(2), cyclohexa-1,3-dienyliodine tetrafluoride (3) and
unreacted xenon difluoride were detected in the mother
liquor. No further fluorine addition to dienes 2 and 3
occurred at 20 8C within the next 3 h. However, after
addition of niobium pentafluoride (stronger fluoride anion
acceptor than HF) to the suspension the fast formation of
perfluorocyclohex-1-enyliodine tetrafluoride (4) resulted in
89% yield (Scheme 1).
These results are in agreement with the following
reaction route (Scheme 5) from iodopentafluorobenzene
(5) to perfluorocyclohexenyliodine tetrafluoride (4) using
xenon difluoride catalysed by Lewis acids (aHF, BF3, and
NbF5).
In the first step iodopentafluorobenzene (5) is rapidly
converted into C6F5IF2 (6) which accidentally corresponds
with the quantitative formation of 6 from 5 and XeF2 in
CH2Cl2 at 20 8C [3]. Pentafluorophenyliodine difluoride
reacts with XeF2 as fluorooxidant on two channels: (a) by the
fluorine addition to the pentafluorophenyl group and (b) to
the IF2 group. The subsequent Lewis acid-catalysed addition
Scheme 1 demonstrates the higher fluorinating ability
of [FXe][NbF6] generated in situ from XeF2 and NbF5
compared to that of the polarised complex [FXeꢁ ꢁ ꢁFꢁ ꢁ ꢁHF]
and offers the opportunity for the aimed formation of 4
directly from iodopentafluorobenzene (5). Indeed, treatment
of 5 with xenon difluoride in the presence of a catalytic
amount (ca. 10 mol.%) of NbF5 in aHF gave 4 in 72% yield
(Scheme 2).
The conversion of iodoarene 5 to cyclohexenyliodine
tetrafluoride 4 (Scheme 2) can primarily proceed as
an oxidative fluorination of the iodine atom (C6F5I !
C6F5IF2 ! C6F5IF4) with the subsequent fluorine addi-
tion to the C C bonds of 1, 2, and 3, respectively
(C6F5IF4 ! C6F7IF4 ! C6F9IF4) (Scheme 1). Alternatively,
the fluorination of the pentafluorophenyl group can run
Scheme 2.

1038
H.J. Frohn, V.V. Bardin / Journal of Fluorine Chemistry 126 (2005) 1036–1043
Scheme 3.
Scheme 4.
of two fluorine atoms to diene C6F7IF2 (7) leads to
cyclohexadienyliodine tetrafluoride 2 (diene 7 did not react
with XeF2 in CH2Cl2 without Lewis acid-catalyst at 50 8C
[12]). 2 and its isomer 3 are also products of the parallel
addition of fluorine to C6F5IF4. Finally, both cyclohexa-
dienyliodine tetrafluorides 2 and 3 undergo oxidative
addition of fluorine across the FC CF fragment to yield
cyclohexenyliodine tetrafluoride 4. The formation of
organoiodine(VII) compounds as well as perfluorocyclo-
hexyliodine tetrafluoride did not occur.
difluoride [7]. 2,3,4,5-Tetrafluorophenyliodine tetrafluoride
(8) was a substrate of particular interest because of the strong
inductive effect of the IF4 group and its weak resonance
effect (sI = 0.98, sR = 0.17 [13]).
Compound 8 did not react with XeF2 in PFB but in the
presence of boron trifluoride polyfluorinated cycloalkenyl-
iodine tetrafluorides were formed. The main products were
2-H-hexafluorocyclohexa-1,4-dienyliodine tetrafluoride (9),
2-H-octafluorocyclohex-1-enyliodine tetrafluoride (10), 6-
H-hexafluorocyclohexa-1,4-dienyliodine tetrafluoride (11)
and 6-H-octafluorocyclohex-1-enyliodine tetrafluoride (12).
In a parallel route, a significant amount of perfluorinated
cycloalkenyliodine tetrafluorides 2, 3, and 4 were formed
(Scheme 6).
Our earlier investigations of reactions of tetrafluoroben-
zenes C6HF4R (R H, F, Br, CF3, NO2 [7], SiMe3 [8],
Xe+[AsF6]ꢀ [5]) with XeF2 and BF3ꢁOEt2 in CH2Cl2 or with
XeF2 in aHF showed that the addition of fluorine to the
polyfluorinated aromatic group was accompanied by the
partial substitution of the hydrogen atom in position 2 or 3 to
substituent R. The hydrogen atom located in position 4 was
not replaced by fluorine in any case. This circumstance was
explained within the framework of the one electron transfer
mechanism induced by the strong fluorooxidant [FXe]+ or a
structurally related polarised species generated from xenon
The reaction of 1-iodo-2,3,5,6-tetrafluorobenzene (13)
with XeF2 (excess) and BF3 in PFB resulted in hydrogen-
containing cycloalkenyliodine tetrafluorides 14, 15, and 16.
Here no substitution of hydrogen by fluorine occurred
(Scheme 7).
Both examples well complete the previous view of the
fluorine addition to polyfluoroaromatic groups [7].
Scheme 5.

H.J. Frohn, V.V. Bardin / Journal of Fluorine Chemistry 126 (2005) 1036–1043
1039
Scheme 6.
Scheme 7.
2.2. Preparation of perfluoroalk-1-enyliodine
tetrafluoride and perfluoroalkyliodine tetrafluoride
by fluorination with XeF2
reaction neither the formation of 1-iodoperfluoro-3-methyl-
butane nor perfluoro-3-methylbutyliodine di- and tetra-
fluoride was detected (Scheme 8).
The formation of perfluorohexyliodine tetrafluoride (20)
from perfluorohexyl iodide (19) and xenon difluoride in the
presence of BF3 shows that this method of fluorination can
even be extended to the class of perfluoroalkyliodine
tetrafluorides (Scheme 9). In summary, the last examples
complete the general character of this route to polyfluori-
nated organoiodine tetrafluorides.
The remarkable peculiarity of all examples discussed
before is the absence of poly- and perfluorocyclohexyliodine
di- and tetrafluorides among the reaction products. This
implies that (a) the oxidative addition of fluorine to iodine
in aryl iodides proceeds much faster than the fluorine
addition across the FC CF and FC CI double bonds in the
polyfluoroaromatic group and (b) that the FC CIFn
fragments (n = 2, 4) resist to the oxidative fluorination
under the conditions of reaction described here. Hence,
these circumstances provide the opportunity to prepare
acyclic perfluoroalk-1-en-1-yliodine tetrafluorides from
the corresponding perfluorinated alkenyl iodides under
similar reaction conditions. To extend the fluorination with
XeF2–Lewis acid on acyclic compounds, we examined
the reaction of 1-iodoperfluoro-3-methylbut-1-enes (cis:
trans = 12:88) (17) with XeF2 in PFB in the presence of
boron trifluoride.
Finally, it should be emphasised that perfluoroorganoio-
dine tetrafluorides RFIF4 resist to the strong protic acid aHF,
to acidified aHF (aHF–NbF5), and to the Lewis acid boron
trifluoride at 20–22 8C for some hours. The only effect of
interaction of RFIF4 with these acids was the broadening of
the IF4 signal in the 19F NMR spectra and the disappearance
of the spin–spin coupling of the IF4 nuclei with CFx ones of
the perfluoroorgano group in RFIF4 (for example, see
Section 4). This phenomenon indicates a fast exchange of
fluoride between RFIF4 and the Lewis acid (fluoride anion
acceptor) without complete ionisation to organoiodo-
nium(V) trifluoride cations. The degree of broadening
increases in the series C6F13IF4 < (CF3)2CFCF CFIF4 <
cyclo-C6F9IF4 which points out the diminishing of the
electron-withdrawing effect of the perfluoroorgano group
The treatment of 17 in PFB with xenon difluoride (two
equivalents) with a slow bubbling of BF3 resulted in
perfluoro-3-methylbut-1-enyliodine tetrafluorides 18 (cis:
trans = 1:9) in high yield. Noteworthy, that at the end of the
Scheme 8.

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H.J. Frohn, V.V. Bardin / Journal of Fluorine Chemistry 126 (2005) 1036–1043
trichlorotrifluoroethane or C6F6. 1-X-nonafluorocyclohex-
enes [14] and 1-X-heptafluorocyclohexadienes [15] were
identified by their 19F NMR spectra.
C6F5IF2 was prepared by a modified low temperature
fluorination of C6F5I in CCl3F [16]. C6F5IF4 was obtained
by reaction of Bi(C6F5)3 and IF5 in MeCN [17].
(CF3)2CFCF CFI [18] was kindly given by Dr. Cherstkov
(INEOS RAN, Russia). Dichloromethane (Baker), acetoni-
Scheme 9.
which is mainly influenced by the number of electron-
wthdrawing fluorine atoms at the carbon atom C(1).
¨
trile (Riedel-deHaen) were purified and dried by standard
procedures. Iodopentafluorobenzene, 2,3,4,5-tetrafluoroio-
dobenzene, 2,3,5,6-tetrafluoroiodobenzene (Bristol Organ-
ics), 1-iodoperfluorohexane (Clariant), 1,1,1,3,3-penta-
fluorobutane (Solvay), and boron trifluoride (Messer
Griesheim) were used as supplied. NbF5 was distilled in
FEP (block copolymer of tetrafluoroethylene and hexa-
fluoropropylene) equipment before use. Anhydrous HF was
stored over CoF3.
3. Conclusions
The fluorooxidant XeF2–BF3 in PFB allows the addition
of fluorine in perfluoroorganyl iodide and perfluoroorga-
noiodine difluoride and finally ends with perfluoroorga-
noiodine tetrafluorides. In case of iodopentafluorobenzene
as starting compound addition of fluorine to the penta-
fluorophenyl group proceeds forming cyclohexadienylio-
dine and cyclohexenyliodine tetrafluorides beside fluorine
addition to iodine. No perfluorocyclohexyliodine tetrafluor-
ide was obtained, even in the presence of the stronger Lewis
acid NbF5 in aHF.
All manipulations were performed in FEP equipment
under an atmosphere of dry argon.
4.1. Preparation of polyfluorocycloalk-1-enyliodine
tetrafluorides
It seems to be a general feature that molecules with the
fragment CF CIF4 do not undergo fluorine addition across
this C C double bond under the action of XeF2 and BF3 or
NbF5. Furthermore this fluorooxidant does not allow
fluorine addition to the IF4 group and formation of the
hitherto unknown organoiodine hexafluorides.
4.1.1. Starting from pentafluorophenyliodine compounds
4.1.1.1. Fluorination of C6F5I (5) with XeF2 and BF3 in
PFB. A solution of 5 (92 mg, 0.31 mmol) in PFB (2 ml) was
cooled to ꢀ13 8C and XeF2 (214 mg, 1.27 mmol) was added
in one portion. Boron trifluoride was slowly bubbled through
the stirred reaction mixture, which was finally allowed to
warm to 20 8C. After 25 min a probe of the colourless
solution showed the presence of 7, 1, 2, 3, and 4 (molar ratio
9:11:60:17:3) (19F NMR). A second portion of XeF2 (47 mg,
total amount 1.54 mmol) was added and the solution was
stirred for further 30 min with bubbling of BF3. The 19F
NMR spectrum showed resonances of 2, 3, and 4 (molar
ratio 76:18:6) beside 7 and IF5 (traces). The solution was
evaporated to dryness under reduced pressure to give a
white solid (128 mg) that consisted of 2 (0.21 mmol), 3
(0.03 mmol) and 4 (0.04 mmol) (molar ratio 2:3:4 =
76:10:14).
Fluorination of perfluoroalkenyl and polyfluoroaryl
iodides, polyfluoroaryliodine di- and tetrafluorides with
XeF2 and Lewis acid (aHF, BF3, NbF5) results in previously
unknown organoiodine compounds, alk-1-enyliodine tetra-
fluorides and cycloalk-1-enyliodine tetrafluorides.
The Lewis acid-catalysed fluorine addition to C6F5IF4
and C6HF4IF4 using xenon difluoride occurs in the same way
as the corresponding addition reactions to pentafluoro-
(C6F5R) and tetrafluorobenzene derivatives (C6HF4R) [6–8].
This means the same or a closely related mechanism of
reaction.
The formation of organoiodine(VII) as well as perfluoro-
cyclohexyliodine tetrafluoride was not detected even under
the action of the strong fluorinating agent XeF2–NbF5–aHF.
Reactions of perfluoroalkyl iodides RFI with XeF2 in
PFB under catalysis of BF3 are a simple and convenient
laboratory route to perfluoroalkyliodine tetrafluorides RFIF4.
4.1.1.2. Fluorination of C6F5I (5) with XeF2 and NbF5 in
aHF. Xenon difluoride (430 mg, 2.54 mmol) and NbF5
(38 mg, 0.20 mmol) were dissolved in aHF (2 ml) at 0 8C
and C6F5I (5) (140 mg, 0.47 mmol) was added in portions.
After 5 min the solution was warmed to 18–20 8C (bath)
and stirred for 1.5 h. To destroy the excess of XeF2, C6F6
(ca. 0.05 ml) was added at 10 8C. This solution was stirred
at 15–17 8C for 10–15 min. The products were extracted
with anhydrous dichloromethane (3 ml) at ꢀ20 8C. The
extract was treated with NaF, the suspension was
centrifuged and the solvent was removed in vacuum to
give 4 (152 mg, 72%).
4. Experimental details
NMR spectra were recorded on a Bruker AVANCE 300
spectrometer (1H at 300.13 MHz and 19F at 282.40 MHz) at
24 8C. The chemical shifts are referenced to TMS (1H)
and CCl3F (19F) [with C6F6 as a secondary reference
(ꢀ162.9 ppm)]. The composition of the reaction mixtures
and the yields of products were determined by 19F NMR
spectroscopy using the internal quantitative standards 1,1,2-
4.1.1.3. Fluorination of C6F5IF2 (6) with XeF2 and BF3 in
PFB. A solution of 6 (111 mg, 0.33 mmol) in PFB (2 ml)

H.J. Frohn, V.V. Bardin / Journal of Fluorine Chemistry 126 (2005) 1036–1043
1041
was cooled to 0 8C and XeF2 (62 mg, 0.36 mmol) was added
in one portion. No reaction was observed within 5 min. Then
BF3 was slowly bubbled through for 2 h at 20 8C.
Precipitation and gas evolution occurred. A second portion
of XeF2 (226 mg, total amount 1.70 mmol) was added and
stirring was continued for 1 h at 20 8C with bubbling of BF3.
The solid part of the suspension dissolved. After addition of
C6F6 (excess) to decompose residual XeF2 the solution was
concentrated under reduced pressure. The solution con-
tained 2, 4 (70:30) (quantitative yield) and IF5 (trace).
Heptafluorocyclohexa-1,4-dienyliodine tetrafluoride (2).
19F NMR (CH2Cl2): d ꢀ5.9 (t 4J(IF4, F6) = 18 Hz, d 4J(IF4,
F2) = 28 Hz, 4F, IF4), ꢀ95.9 (m, 2F, F6,6), ꢀ96.9 (m, 1F, F2),
warmed to 20 8C until xenon evolution came to an end.
Finally the suspension was stirred at 20 8C for 20 min. The
19F NMR spectrum contained resonances of 2, 3, and XeF2
(molar ratio 2:1:1.3) beside aHF and a trace of IF5. No
changes occurred when the suspension was kept at 20 8C for
3 h. The suspension was cooled to ꢀ5 8C, NbF5 (70 mg,
0.37 mmol) was added and the reaction mixture was stirred
at 20 8C for 15 min. Hydrogen fluoride was removed in
vacuum, the residue was extracted with dichloromethane
and cyclohexene 4 (white solid) (211 mg, 89%) was
obtained after removal of the solvent in vacuum (19F NMR).
4.1.2. Starting from tetrafluorophenyliodine compounds
4.1.2.1. Synthesis of 2,3,4,5-tetrafluorophenyliodine tetra-
fluoride (8). 8 was prepared from 2,3,4,5-tetrafluoroiodo-
benzene and XeF2 via 2,3,4,5-tetrafluorophenyliodine
difluoride according to the procedure described for the
preparation of pentafluorophenyliodine tetrafluoride [3].
2,3,4,5-Tetrafluorophenyliodine difluoride. 2,3,4,5-Tetra-
fluoroiodobenzene (580 mg, 2.10 mmol) and XeF2 (395 mg,
2.31 mmol) were heated at 40–45 8C (bath) for 1 h under an
atmosphere of dry argon. After cooling to 20 8C the product
2,3,4,5-C6HF4IF2 (white solid) was obtained (642 mg,
97%).
5
4
3
ꢀ110.1 (t J(F3, F6) = 3 Hz, d J(F3, F5) = 10 Hz, d J(F3,
F4) = 20 Hz, d 3J(F3, F2) = 24 Hz, 2F, F3,3), ꢀ148.8 (m, 1F,
3
3
F5), ꢀ158.2 (d J(F4, F5) = 5 Hz, t J(F4, F3) = 21 Hz, t
4J(F4, F6) = 10 Hz, 1F, F4).
Heptafluorocyclohexa-1,4-dienyliodine tetrafluoride (2).
19F NMR (PFB, saturated with BF3): d ꢀ95.9 (t 5J(F6,
4
4
F3) = 4 Hz, d J(F6, F2) = 10 Hz, d J(F6, F4) = 10 Hz, d
3J(F6, F5) = 21 Hz, 2F, F6,6), ꢀ97.6 (d J(F2, F5) = 1 Hz, d
5
4J(F2, F4) = 3 Hz, t 4J(F2, F6) = 10 Hz, t 3J(F2, F3) = 22 Hz,
1F, F2), ꢀ110.8 (t 5J(F3, F6) = 4 Hz, d 4J(F3, F5) = 11 Hz, d
3J(F3, F4) = 19 Hz, d 3J(F3, F2) = 22 Hz, 2F, F3,3), ꢀ150.6 (d
5J(F5, F2) = 1 Hz, d 3J(F5, F4) = 4 Hz, t 4J(F5, F3) = 11 Hz, t
3
19F NMR (CH2Cl2): d ꢀ120.9 (d J(F2, F3) = 20 Hz, d
3J(F5, F6) = 21 Hz, 1F, F5), ꢀ160.1 (d J(F4, F2) = 3 Hz, d
4J(F2, F4) = 4 Hz, d J(F2, F5) = 8 Hz, d J(F2, H6) = 5 Hz,
4
5
4
3J(F4, F5) = 4 Hz, t J(F4, F6) = 10 Hz, 1F, F4).
1F, F2), ꢀ134.9 (d 4J(F5, F3) = 3 Hz, d 3J(F5, F4) = 20 Hz, d
4
5
Heptafluorocyclohexa-1,3-dienyliodine tetrafluoride (3).
19F NMR (CH2Cl2): d ꢀ8.6 (t 4J(IF4, F6) = 14 Hz, d 4J(IF4,
F2) = 23 Hz, 4F, IF4), ꢀ89.8 (m, 1F, F2), ꢀ113.2 (m, 2F,
F6,6), ꢀ126.3 (m, d 4J(F5, F3) = 15 Hz, d 3J(F5, F4) = 19 Hz,
2F, F5,5), ꢀ144.2 (t 3J(F4, F5) = 18 Hz, d 4J(F4, F2) = 18 Hz,
1F, F4), ꢀ148.3 (d 3J(F3, F2) = 9 Hz, t 4J(F3, F5) = 15 Hz, 1F,
F3).
3J(F5, H6) = 13 Hz, d J(F5, F2) = 8 Hz, 1F, F5), ꢀ146.0 (d
3J(F4, F5) = 20 Hz, d 3J(F4, F3) = 19 Hz, d 4J(F4, H6) = 8 Hz,
d 4J(F4, F2) = 4 Hz, 1F, F4), ꢀ150.0 (d 3J(F3, F2) = 20 Hz, d
3J(F3, F4) = 19 Hz, d 5J(F3, H6) = 4 Hz, d 4J(F3, F5) = 3 Hz,
1F, F3), ꢀ161.1 (s, 2F, IF2); 1H NMR (CH2Cl2): d 7.94 (m,
1H, H6).
2,3,4,5-Tetrafluorophenyliodine tetrafluoride (8). 2,3,4,5-
Tetrafluorophenyliodine difluoride (573 mg, 1.82 mmol)
and XeF2 (450 mg, 2.66 mmol) were heated at 90–110 8C
(bath) for 12 h under an atmosphere of dry argon. The melt
was cooled to 20 8C and treated in vacuum for 4 h yielding
2,3,4,5-C6HF4IF4 (white solid) (602 mg, 94%).
Heptafluorocyclohexa-1,3-dienyliodine tetrafluoride (3).
3
19F NMR (PFB, saturated with BF3): d ꢀ90.8 (d J(F2,
4
3
F3) = 6 Hz, d J(F2, F4) = 17 Hz, t J(F2, F6) = 17 Hz, 1F,
F2), ꢀ113.1 (m, d 4J(F6, F4) = 4 Hz, d 4J(F6, F2) = 17 Hz, 2F,
F6,6), ꢀ126.9 (m, d 4J(F5, F3) = 14 Hz, d 3J(F5, F4) = 18 Hz,
2F, F5,5), ꢀ146.8 (t 4J(F4, F6) = 4 Hz, t 3J(F4, F5) = 18 Hz, d
19F NMR (PFB): d ꢀ14.1 (d 4J(IF4, F2) = 21 Hz, 4F, IF4),
3
4
3
4J(F4, F2) = 17 Hz, 1F, F4), ꢀ150.3 (d J(F3, F2) = 6 Hz, t
ꢀ129.8 (quint J(F2, IF4) = 21 Hz, d J(F2, F3) = 19 Hz, d
5J(F2, F5) = 10 Hz, d 4J(F2, F4) = 11 Hz, d 4J(F2, H6) = 5 Hz,
1F, F2), ꢀ136.2 (d 5J(F5, F2) = 10 Hz, d 4J(F5, F3) = 4 Hz, d
3J(F5, F4) = 19 Hz, d 3J(F5, H6) = 10 Hz, 1F, F5), ꢀ145.9 (d
4J(F3, F5) = 14 Hz, 1F, F3).
Nonafluorocyclohex-1-enyliodine tetrafluoride (4). 19F
4
4
NMR (CH2Cl2): d ꢀ5.1 (t J(IF4, F6) = 17 Hz, d J(IF4,
F2) = 28 Hz, 4F, IF4), ꢀ93.7 (m, 1F, F2), ꢀ104.0 (m, 2F,
F6,6), ꢀ117.1 (m, d 3J(F3, F2) = 25 Hz, 2F, F3,3), ꢀ133.1 (m,
2F, F5,5), ꢀ133.6 (m, 2F, F4,4).
3J(F4, F3) = 19 Hz,
d
3J(F4, F5) = 19 Hz,
d
4J(F4,
4
F2) = 11 Hz, d J(F4, H6) = 8 Hz, 1F, F4), ꢀ152.0 (m, d
3J(F3, F2) = 19 Hz, d J(F3, F4) = 19 Hz, 1F, F3); H NMR
(CH2Cl2): d 7.91 (m, 1H, H6).
3
1
Nonafluorocyclohex-1-enyliodine tetrafluoride (4). 19F
NMR (PFB, saturated with BF3): d ꢀ94.4 (m, 1F, F2),
3
ꢀ103.8 (m, 2F, F6,6), ꢀ117.7 (m, d J(F3, F2) = 24 Hz, 2F,
4.1.2.2. Fluorination of 2,3,4,5-C6HF4IF4 (8) with XeF2
and BF3 in PFB. XeF2 (100 mg, 0.59 mmol) was added to a
stirred suspension of 8 (204 mg, 0.58 mmol) in PFB (2 ml)
at 20 8C. The reaction mixture was stirred for further 3 min
but no gas evolution could be observed. The suspension was
cooled to 0 8C (bath) and a slight flow of BF3 was bubbled
through and caused dissolution of 8. After 5 min a second
F3,3), ꢀ133.5 (m, 2F, F5,5), ꢀ134.0 (m, 2F, F4,4).
4.1.1.4. Fluorination of C6F5IF4 (1) with XeF2 in aHF. A
suspension of 1 (199 mg, 0.53 mmol) in aHF (0.3 ml) was
cooled to ꢀ5 8C and XeF2 (182 mg, 1.07 mmol) was added
in portions. After each addition, the reaction mixture was

1042
H.J. Frohn, V.V. Bardin / Journal of Fluorine Chemistry 126 (2005) 1036–1043
portion of XeF2 (250 mg, total amount 2.07 mmol) was
added. The solution was stirred at 20 8C for 1 h with a slow
bubbling of BF3 and then treated with C6F6 (ca. 0.05 ml) to
reduce the surplus of XeF2 and after 15 min with dry NaF to
remove BF3. The mother liquor was separated after
centrifugation. The 19F NMR spectrum showed the
formation of 2 (0.10 mmol), 3 (0.02 mmol), 4 (0.02 mmol),
9 (0.25 mmol), 10 (0.06 mmol), 11 (0.04 mmol), 12
(0.05 mmol), and IF5 (0.05 mmol) beside 1,4-C6F8 (from
C6F6) and unreacted C6F6 and XeF2 (0.33 mmol). When this
solution was maintained at 20 8C for further 48 h, no
changes in the 19F NMR spectrum were observed.
C6F6) and XeF2 (0.34 mmol). Continued supply of BF3 into
the solution for 1 h at 24 8C led to the disappearance of XeF2
and the partial conversion of 15 into 16 (molar ratio
14:15:16 = 67:6:27) (19F NMR).
4-H-Hexafluorocyclohexa-1,4-dienyliodine tetrafluoride
(14). 19F NMR (PFB): d ꢀ6.7 (t 4J(IF4, F6) = 18 Hz, d
4J(IF4, F2) = 24 Hz, 4F, IF4), ꢀ94.7 (m, 1F, F2), ꢀ97.3 (m, 2F,
F6,6), ꢀ98.8 (t 5J(F3, F6) = 3 Hz, d 3J(F3, H4) = 5 Hz, d 4J(F3,
F5) = 12 Hz, d 3J(F3, F2) = 23 Hz, 2F, F3,3), ꢀ120.9 (d 5J(F5,
F2) = 2 Hz, d 3J(F5, H4) = 10 Hz, t 4J(F5, F3) = 12 Hz, t 3J(F5,
F6) = 21 Hz, 1F, F5); 1H NMR (PFB): d 6.00 (m, 1H, H4).
4-H-Hexafluorocyclohexa-1,4-dienyliodine tetrafluoride
(14). 19F NMR (PFB saturated with BF3): d ꢀ94.7 (d 5J(F2,
F5) = 2 Hz, d 4J(F2, H4) = 6 Hz, t 4J(F2, F6) = 11 Hz, t 3J(F2,
2-H-Hexafluorocyclohexa-1,4-dienyliodine tetrafluoride
(9). 19F NMR (PFB): d ꢀ12.9 (t 4J(IF4, F6) = 15 Hz, 4F, IF4),
5
3
4
5
ꢀ101.1 (m, 2F, F6,6), ꢀ103.0 (t J(F3, F6) = 4 Hz, d J(F3,
F3) = 23 Hz, 1F, F2), ꢀ97.3 (d J(F6, H4) = 2 Hz, t J(F6,
H2) = 5 Hz, d J(F3, F5) = 11 Hz, d J(F3, F4) = 20 Hz, 2F,
F3) = 3 Hz, d J(F6, F2) = 11 Hz, d J(F6, F5) = 21 Hz, 2F,
F6,6), ꢀ98.8 (t 5J(F3, F6) = 3 Hz, d 3J(F3, H4) = 5 Hz, d
4J(F3, F5) = 12 Hz, d 3J(F3, F2) = 23 Hz, 2F, F3,3), ꢀ120.9 (d
5J(F5, F2) = 2 Hz, d 3J(F5, H4) = 10 Hz, t 4J(F5, F3) = 12 Hz,
4
3
4
3
F3,3), ꢀ153.0 (d J(F4, F5) = 3 Hz, t J(F4, F6) = 11 Hz, t
3
4
3J(F4, F3) = 20 Hz, 1F, F4), ꢀ157.1 (d J(F5, F4) = 3 Hz, t
3
4J(F5, F3) = 11 Hz, t 3J(F5, F6) = 20 Hz, d 5J(F5, H2) = 6 Hz,
1F, F5); H NMR (PFB): d 7.59 (m, 1H, H2).
t
3J(F5, F6) = 21 Hz, 1F, F5). The broad resonance (t1/
1
2-H-Octafluorocyclohex-1-enyliodine tetrafluoride (10).
2 ꢃ 400 Hz) of the IF4 group was located at ꢀ6.6 ppm.
4-H-Hexafluorocyclohexa-1,3-dienyliodine tetrafluoride
(15). 19F NMR (PFB): d ꢀ9.0 (t 4J(IF4, F6) = 14 Hz, d 4J(IF4,
F2) = 23 Hz, 4F, IF4), ꢀ92.0 (m, 1F, F2), ꢀ113.5 (m, 2F,
4
19F NMR (PFB): d ꢀ11.5 (t J(IF4, F6) = 15 Hz, 4F, IF4),
ꢀ107.3 (m, 2F, F6,6), ꢀ108.9 (m, 2F, F3,3), ꢀ133.8 (m, 2F)
and ꢀ134.6 (m, 2F) (F4,4 and F5,5); 1H NMR (PFB): d 7.58
(m, 1H, H2).
3
5
F6,6), ꢀ117.0 (d J(F5, H4) = 5 Hz, d J(F5, F2) = 5 Hz, d
4J(F5, F3) = 16 Hz, 2F, F5,5), ꢀ119.9 (d 3J(F3, F2) = 8 Hz, t
5J(F3, F6) = 1 Hz, d 3J(F3, H4) = 7 Hz, t 4J(F3, F5) = 16 Hz,
6-H-Hexafluorocyclohexa-1,4-dienyliodine tetrafluoride
4
(11). 19F NMR (PFB): d ꢀ15.4 (d J(IF4, F6) = 14 Hz, d
4J(IF4, F2) = 24 Hz, 4F, IF4), ꢀ99.7 (m, 1F, F2), ꢀ105.9 (m,
1F, F3); H NMR (PFB): d 6.00 (m, 1H, H4).
1
2
2
d J(F3A, F3B) = 305 Hz, 1F, F3A), ꢀ111.3 (m, d J(F3B
,
4-H-Hexafluorocyclohexa-1,3-dienyliodine tetrafluoride
3
F3A) = 305 Hz, 1F, F3B), ꢀ136.3 (m, d J(F5, F6) = 32 Hz,
(15).19F NMR (PFB saturated with BF3): d ꢀ92.0 (d J(F2,
3
1F, F5), ꢀ160.0 (m, 1F, F4), ꢀ173.0 (m, 1F, F6); H NMR
F3) = 8 Hz, d 4J(F2, H4) = 7 Hz, t 4J(F2, F6) = 17 Hz, 1F, F2),
ꢀ113.5 (m, d 4J(F6, F2) = 17 Hz, 2F, F6,6), ꢀ117.0 (d 3J(F5,
1
(PFB): d 6.34 (m, d J(H6, F6) = 47 Hz, 1H, H6).
2
5
4
6-H-Octafluorocyclohex-1-enyliodine tetrafluoride (12).
H4) = 5 Hz, d J(F5, F2) = 5 Hz, d J(F5, F3) = 16 Hz, 2F,
19F NMR (PFB): d ꢀ16.5 (d J(IF4, F6) = 6 Hz, d J(IF4,
F2) = 23 Hz, 4F, IF4), ꢀ97.1 (m, 1F, F2), ꢀ110.4 (m, d
3J(F3A, F2) = 28 Hz, d 2J(F3A, F3B) = 295 Hz, 1F, F3A),
ꢀ125.8 (m, d 2J(F3B, F3A) = 295 Hz, 1F, F3B), ꢀ122.9 (m, d
F5,5), ꢀ119.9 (d J(F3, F2) = 8 Hz, t J(F3, F6) = 1 Hz, d
4
4
3
5
3J(F3, H4) = 7 Hz, t J(F3, F5) = 16 Hz, 1F, F3). The broad
4
resonance (t1/2 ꢃ 400 Hz) of the IF4 group was located at
ꢀ6.6 ppm.
2J(F4A, F4B) = 286 Hz, 1F, F4A), ꢀ131.0 (m, d 2J(F4B
,
,
4-H-Octafluorocyclohex-1-enyliodine tetrafluoride (16).
F4A) = 286 Hz, 1F, F4B), ꢀ123.1 (m,
d
2J(F5A
19F NMR (PFB): d ꢀ5.8 (d J(IF4, F6A) = 15 Hz, d J(IF4,
F6B) = 18 Hz, d 4J(IF4, F2) = 27 Hz, 4F, IF4), ꢀ94.7 (m, 1F,
F2), ꢀ99.4 (m, d 2J(F6A, F6B) = 287 Hz, 1F, F6A), ꢀ107.9 (m,
4
4
F5B) = 278 Hz, 1F, F5A), ꢀ140.8 (m, d 2J(F5B, F5A) =
278 Hz, 1F, F5B), ꢀ178.2 (m, 1F, F6) (the assignment of F4
1
2
2
2
and F5 is tentative); H NMR (PFB): d 6.07 (m, d J(H6,
d J(F6B, F6A) = 287 Hz, 1F, F6B), ꢀ106.3 (m, d J(F3A
,
F6) = 46 Hz, 1H, H6).
F3B) = 298 Hz, 1F, F3A), ꢀ115.3 (m, d 2J(F3B, F3A) = 298 Hz,
1F, F3B), ꢀ127.8 (m, d J(F5A, F5B) = 266 Hz, 1F, F5A),
2
4.1.2.3. Fluorination of 2,3,5,6-C6HF4I (13) with XeF2 and
BF3 in PFB. XeF2 (370 mg, 2.18 mmol) was added to the
stirred solution of 13 (122 mg, 0.44 mmol) in PFB (2 ml) at
ꢀ15 8C and a slight flow of BF3 was passed through the
solution. After 15 min the bath was removed and the
colourless solution was stirred at 24 8C for 1 h with a slow
bubbling of BF3. Hexafluorobenzene (ca. 0.05 ml) was
added and the solution was stirred for further 30 min. The
solution was concentrated under reduced pressure to ca.
1.5 ml volume and treated with dry NaF. The 19F NMR
spectrum showed resonances of 14, 15, and 16 (68:11:21)
(total yield 0.38 mmol) beside IF5 (trace), 1,4-C6F8 (from
ꢀ130.2 (m, d 2J(F5B, F5A) = 266 Hz, 1F, F5B), ꢀ222.3 (m, d
1
2J(F4, H4) = 45 Hz, 1F, F4); H NMR (PFB): d 5.17 (m, d
2J(H4, F4) = 45 Hz, 1H, H4).
4-H-Octafluorocyclohex-1-enyliodine tetrafluoride (16).
19F NMR (PFB saturated with BF3): d ꢀ94.7 (m, 1F, F2),
2
ꢀ99.4 (m, d J(F6A, F6B) = 287 Hz, 1F, F6A), ꢀ107.9 (m, d
2J(F6B, F6A) = 287 Hz, 1F, F6B), ꢀ106.3 (m, d 2J(F3A
,
F3B) = 298 Hz, 1F, F3A), ꢀ115.3 (m, d 2J(F3B, F3A) = 298 Hz,
1F, F3B), ꢀ127.8 (m, d J(F5A, F5B) = 266 Hz, 1F, F5A),
2
ꢀ130.2 (m, d J(F5B, F5A) 266 Hz, 1F, F5B), ꢀ222.3 (m, d
2
2J(F4, H4) = 45 Hz, 1F, F4). The broad resonance (t1/
2 ꢃ 400 Hz) of the IF4 group was located at ꢀ6.6 ppm.

H.J. Frohn, V.V. Bardin / Journal of Fluorine Chemistry 126 (2005) 1036–1043
1043
4.2. Preparation of perfluoroalk-1-enyliodine and
perfluoroalkyliodine tetrafluoride
spectrum of its solution in PFB showed the formation of 20
in quantitative yield.
Perfluorohexyliodine tetrafluoride (20). 19F NMR (PFB):
d ꢀ27.7 (apparent pentet 4F, IF4), ꢀ81.4 (t 3J(F6, F5) = 2 Hz,
t 4J(F6, F4) = 10 Hz, 3F, F6,6,6), ꢀ82.0 (m, 2F, F1,1), ꢀ119.5
(m, 2F, F2,2), ꢀ121.2 (m, 2F) and ꢀ122.4 (m, 2F) (F3,3 and
F4,4), ꢀ126.2 (m, 2F, F5,5). In the presence of BF3 (24 8C)
the resonance of the IF4 group at ꢀ27.7 ppm became a broad
singlet (t1/2 = 78 Hz) whereas the position and multiplicity
of all other resonances did not change.
4.2.1. Fluorination of (CF3)2CFCF CFI (17) with XeF2
and BF3 in PFB
XeF2 (497 mg, 2.94 mmol) was added to a stirred
solution of 17 (495 mg, 1.38 mmol) (cis:trans = 12:88) in
PFB (3 ml) at 20 8C. After cooling to ꢀ20 8C (bath) a slight
flow of BF3 was bubbled through and immediately a white
suspension was formed. After 3 min the suspension was
allowed to warm to 25 8C. Dissolution of the solid
proceeded. The slow bubbling of BF3 was continued for
1 h with stirring. The solution was treated with C6F6 (ca.
0.02 ml) and after 5 min all volatile materials were removed in
vacuum at 25 8C to give 500 mg (83%) of (CF3)2CFCF CFIF4
(18) (cis:trans = 1:9).
Acknowledgements
We gratefully acknowledge financial support by the
Deutsche Forschungsgemeinschaft and the Fonds der
Chemischen Industrie and generous donation of chemicals
by Solvay Fluor und Derivate GmbH.
trans-Perfluoro-3-methylbut-1-enyliodine tetrafluoride
(trans-18). 19F NMR (CH2Cl2): d ꢀ19.7 (d 4J(IF4,
F2) = 18 Hz, 4F, IF4), ꢀ75.5 (d 5J(CF3, F1) = 4 Hz, d
4J(CF3, F2) = 8 Hz, d 3J(CF3, F3) = 8 Hz, 6F, CF3), ꢀ129.7
4
3
(m, d J(F1, F3) = 50 Hz, d J(F1, F2) = 135 Hz, 1F, F1),
ꢀ145.0 (m, d J(F2, F1) = 135 Hz, 1F, F2), ꢀ187.3 (sept
3
References
3J(F3, CF3) = 8 Hz,
d d
3J(F3, F2) = 11 Hz, 4J(F3,
[1] (a) P.J. Stang, V.V. Zhdankin, Chem. Rev. 96 (1996) 1123–1178;
(b) A. Varvoglis, The Organic Chemistry of Polycoordinated Iodine,
VCH Publishers, New York, 1992;
F1) = 50 Hz, 1F, F3).
trans-Perfluoro-3-methylbut-1-enyliodine tetrafluoride
(trans-18). 19F NMR (PFB saturated with BF3): d ꢀ19.7
(br, 4F, IF4), ꢀ75.6 (d 5J(CF3, F1) = 4 Hz, d 4J(CF3,
(c) A. Varvoglis, Hypervalent Iodine in Organic Synthesis, Academic
Press, London, 1997.
3
F2) = 8 Hz, d J(CF3, F3) = 8 Hz, 6F, CF3), ꢀ129.8 (sept
[2] J.A. Berry, G. Oates, J.M. Winfield, J. Chem. Soc. Dalton Trans.
(1974) 509–511.
5J(F1, CF3) = 4 Hz,
d
4J(F1, F3) = 50 Hz,
d
3J(F1,
[3] I.I. Maletina, V.V. Orda, N.N. Aleinikov, B.L. Korsunskii, L.M.
Yagupolskii, J. Org. Chem. USSR 12 (1976) 1364 (Eng. Transl.).
[4] H.-J. Frohn, V.V. Bardin, J. Chem. Soc. Chem. Commun. (1993) 1072–
1074.
3
F2) = 135 Hz, 1F, F1), ꢀ145.1 (m, d J(F2, F1) = 135 Hz,
1F, F2), ꢀ187.5 (sept 3J(F3, CF3) = 8 Hz, d 3J(F3,
4
F2) = 11 Hz, d J(F3, F1) = 50 Hz, 1F, F3).
cis-Perfluoro-3-methylbut-1-enyliodine
[5] H.-J. Frohn, V.V. Bardin, Z. Naturforsch. 53B (1998) 562–564.
[6] V.V. Bardin, H.-J. Frohn, J. Fluorine Chem. 60 (1993) 141–151.
[7] V.V. Bardin, L.N. Shchegoleva, H.-J. Frohn, J. Fluorine Chem. 77
(1996) 153–159.
tetrafluoride
(cis-18). 19F NMR (CH2Cl2): –12.3 (d 4J(IF4,
d
F2) = 41 Hz, 4F, IF4), ꢀ74.6 (d 3J(CF3, F3) = 9 Hz, d
4J(CF3, F2) = 9 Hz, 6F, CF3), ꢀ109.3 (d 3J(F1, F2) = 36 Hz,
1F, F1), ꢀ134.9 (m, 1F, F2), ꢀ184.3 (m, 1F, F3).
[8] V.V. Bardin, H.-J. Frohn, J. Fluorine Chem. 90 (1998) 93–96.
[9] V.V. Bardin, G.G. Furin, G.G. Yakobson, J. Org. Chem. USSR 18
(1982) 525–530 (Eng. Transl.).
cis-Perfluoro-3-methylbut-1-enyliodine
tetrafluoride
[10] Preliminary communication: V.V. Bardin, H.-J. Frohn, P. Barthen, in:
12th Eur. Symp. on Fluorine Chemistry, Berlin (Germany), 29
August–2 September, 1998, PII-21.
(cis-18). 19F NMR (PFB saturated with BF3): d ꢀ12.4
(br, 4F, IF4), ꢀ74.7 (d 3J(CF3, F3) = 7 Hz, d 4J(CF3,
F2) = 11 Hz, 6F, CF3), ꢀ109.3 (d 3J(F1, F2) = 36 Hz, 1F, F1),
ꢀ135.0 (sept 4J(F2, CF3) = 11 Hz, d 3J(F2, F1) = 36 Hz, 1F,
F2), ꢀ184.5 (m, 1F, F3).
[11] The use of PFB in preference to widely used dichloromethane for
reactions of organic compounds with xenon difluoride in the presence
of Lewis acids was discussed in Ref. [19].
[12] H.-J. Frohn, R. Nielinger, J. Fluorine Chem. 77 (1996) 143–146.
[13] C. Hansch, A. Leo, R.W. Taft, Chem. Rev. 91 (1991) 165–195.
[14] S.F. Campbell, A.G. Hudson, E.F. Mooney, A.E. Pedler, R. Stephens,
K.N. Wood, Spectrochim. Acta 23A (1967) 2119–2125.
[15] V.V. Bardin, J. Fluorine Chem. 89 (1998) 195–211.
[16] F. Bailly, P. Barthen, W. Breuer, H.-J. Frohn, M. Giesen, J. Helber, G.
Henkel, A. Priwitzer, Z. Anorg. Allg. Chem. 626 (2000) 1406–
1413.
4.2.2. Fluorination of C6F13I (19) with XeF2 and
BF3 in PFB
Xenon difluoride (204 mg, 1.20 mmol) was added to a
solution of 19 (223 mg, 0.50 mmol) in PFB (2 ml) and the
suspension was stirred for 10 min at 25 8C. No reaction
occurred. The suspension was cooled to ꢀ5 8C and BF3 was
bubbled through with stirring. Immediately white slurry was
formed. After warming to 25 8C the solid dissolved and
the colourless solution was stirred for 1 h with bubbling of
BF3. To destroy the excess of XeF2, hexafluorobenzene
(70 mg, 0.37 mmol) was added. All volatile materials were
evaporated in vacuum to give viscous oil. The 19F NMR
¨ ¨
[17] H.-J. Frohn, S. Gorg, G. Henkel, M. Lage, Z. Anorg. Allg. Chem. 621
(1995) 1251–1256.
[18] V.F. Cherstkov, M.V. Galakhov, S.R. Sterlin, L.S. German, I.L.
Knunyants, Izv. AN SSSR. Ser. Khim. (1986) 119–122;
V.F. Cherstkov, M.V. Galakhov, S.R. Sterlin, L.S. German, I.L.
Knunyants, Chem. Abstr. 106 (1986) 17830.
[19] H.-J. Frohn, N.Yu. Adonin, V.V. Bardin, Z. Anorg. Allg. Chem. 629
(2003) 2499–2508.